Electric power transmission circuit



T. S. JONES ELECTRIC POWER TRANSMISSION cmcun Filed Fb. 2, 1959 N N N Q: I I

ALLA

- W4 fi ATTORNEY IN "7W4...

AAAALL Feb. 17, 1942.

Patented Feb. 1 7, 1942 ELECTRIC POWER TRANSMISSION CIRCUIT Townsend S. Jones, Great Neck, N. Y., assignor to Hazeltine Corporation, a corporation of Delaware ,iipplication February 2, 1939, Serial No. 254,290

. I 11 Claims. r This invention relates to a transmission circuit.

' One mode of utilizing the circuit is in connec- ,tion' with a portable radio set whereby said set maybeoperated from batteries, or from direct or alternating house supply current.'without re gard'tothe polarity of the house current connectioiiplug; and whereby said source or supply will fbeautomaticallyshiited from battery to house current, and from house current to battery. upon rtion or withdrawal of a house current connection plug, without the manual operation of paratus oi'thiskind. adapted to receiver to be operated either as any switch other than the usual switch for turning a radio set on or oil.

An object of the'invention is to provide apenable a radio a portable set from batteries-enclosed with-it in a unitary casing, or independently oi'th batteries through connection with the regular electric circuit of a house irrespective'oi whether it supplies alternating or direct current. The parts of the apparatus are so constructed and related'that, when the apparatus is connected to a house circuit the batteries cease tobe'operative as soonas the house circuit becomes operative, and become operative again immediately to continue reception when the house circuit'is disconnected.

Another object is to provide means by which either an alternating or direct current supply circuit can be utilized to transmit current to the receiver, such that no precautions are demanded when direct current is utilized, and no additional lappliancesuch as a polarized connector, is required to avoid joining the high potential side of the supply circuit to the wrong side of the receiver, but onthe contrary, an ordinaryconnector plug suilices to ensure the correct operative connection of the apparatus to the receiver regardless of which 01 the terminals of the plug are engaged with the positive or negative side of said supply circuit. Therefore, no risk oi damage, which might ensue if the return circuits of the receiver were exposed directly to any potential in the house-current"circuit, is incurred, and the inconvenience oi having to withdraw the plug, turn it around and reinsert it, is also avoided.

A further object is to provide apparatus oi. the

kind described above, in which a receiver is connected to batteries and at the same time the circuit oi the apparatus is prepared for connection to a house current supply circuit, merely by tuming on theordinary on and "011 switch of a a radio receiver. No selective manipulation of the switch is necessary, but 'a longas it is in the less and 'until a plug for connecting the apparatus to a house circuit is inserted into an outlet ocket of such a circuit. Then the house current flows into the apparatus, and the battery circuits are broken automatically and without the manual operation of any switch'by' means energized as soon as the circuit of thehouse current supply to said apparatus is completed and becomes operative;

An additional object of the invention is to pro- 'Vide an apparatus having suitable means for indicating when the batteries havebeen rendered inoperative and current from thehouse supply is effective in the operation of the receiver.

Other objects and advantages will be made clear in the following description taken in connection with the accompanying drawing showing a preferred form in which the invention is embodied; but the accompanying disclosure is' for illustration only and many variations may be adopted within the scope of the invention.

In accordance with the present invention, there is provided, in a radio receiver including vacuum tube in the signal-translating channel thereof,

a battery circuit for supplying power to the tubes to operate the receiver, a power-supply circuit connectible to a Power line for supplying power to the tubes to operate the receiver, and means for selectively connecting the battery circuit or the power-supply circuit to the tubes. The arrangement' also comprises means responsive to on" position the batteries will work the set 1111- the energization of the power-supply circuit i'rom a power line for actuating the above mentioned connecting means to disconnect the battery circuit from the tubes during the operation of the receiver by power from the power line.

Specifically in carrying-out my invention I provide a circuit which may be energized either from batteries or from house current and will have the same bias voltage impressed upon the grids of the tubes irrespective of which source of supply is utilized. I accomplish this result by means or a bridge rectifier and a divided resistance disposed in such a manner that the power supply conductors leading from the battery ar connected to the same terminals as the power supply conductors leading irom the house current supply through the rectifier and whereby, when house supply is utilized the current flows through only part of the resistor whereas it flows through the entire resistor when battery supply is utilized.

The invention will best be understood ii the following description is read in connection with the accompanying drawing whichin Figure 1 h......-.s......a

battery current.

shows an embodiment of the invention for supplying power to a radio receiver.

Numerals i and 2 indicat connection points for a battery of low voltage to supply heating current to the filaments or cathodes of several vacuum tubes attached to terminals 3 and 4; and 5 and '6 are connection points for a battery of higher voltage to supply current to the plates or anodes of the tubes, which are united to the 'ior obtaining the desired result may also be housed within the casing of the receiver set. The

wires 8 and 3 may carry at their ends remote from the rectifier the usual two-prong plug l2, to be conveniently inserted into a wall outlet and thus connect the apparatus to either alternating or direct'house current.

The positive pole oi the output 0! the bridge rectifier is indicated at l3 and the negative at I I4. The tubes of the rectifier are so related that the'tube Ha has an anode l5 and cathod l6 Joined together; the junction being united to the lead 9; it also has asecond cathode ll, united to thepole I3. The other tube, llb, has an anode l5 joined to a cathode l6 and both united to the lead 8, and this tube has another cathode ll joined to the pole l3. In each tube ther is a second anode l8, and these anodes are connect ed together outside-the tubes, and attached to the pole l4. Across the wires 8 and 3 are filament resistances I! in series with the rectifier filaments 20, which in practice will be inside the tubes, one associated with each pair of anodes and cathodes I5-l'l, or-IS-IS.

At 2| is a relay coil-connected across the positive and negative output poles I3 and I4, or the rectifier as will be described, the contact points 24a, 24b of the relay being associated with the battery circuits and points 24A, 243 being associated with the rectifier circuit.

From the battery terminal 1 current goes to the terminal 3 througha lead 23 and a movable contact 25 connected to said terminal and normally resting upon the fixed contact 240 attached to thelead 23. Also a conductor 26 leads from the terminal 5 to the terminal I, and in the line of this conductor is a similar fixed contact 24b and a movable contact 25'. Both movable contacts 25 and 2 5 are controlled by the relay coil 2|, as indicated by the dot'-and-dash line connecting said contacts. 01 course when the engage the terminals 24A and 24B respectively. The battery circuits will then be opened and current from the rectifier will be transmitted to the catholic. and anodes of the tubes in the set. When, however, the rectifier circuits are not energized, the batteries will supply the tube circuits connected to terminals 3,-4 and I; and suitable springs (not shown) may be mounted and connected to the contacts 25 and 25 to cause them to move into position to close the battery circuits whenever the coil 2! is not receiving current from the rectifier in.

In the line of the conductor 8 and of the wires ac and 3| connecting the terminals 4 and 2 are a pair of switch arms 32. These switch arms 32 constitute an ordinary, usually manual, connector switch to open and close the circuit oi the cathode battery and the circuit leading from the connector plug i2 through leads 8 and 3 to the rectifier Ill. The switch arms can be joined by a link with a button or knob thereon which extends to the outside of the set so that the receiver may be conveniently turned "on" and oil. When the receiver is not in use the switch arms 32 are in off position. With the switch arms at the switch 32 in closed position, battery current will be supplied to the tubes whenever the terminals of leads 8 and 5 are not connected to the house current. When terminals of leads 5 contacts 25 and 25' are in position to close the. circuits from the terminals l and 5, to the filaments and anodes, the tubes are energized by At21 is a conductor leading from the ,positive side 01 the rectifier, with abranch 28A runnin 1 to a fixed terminal 24A adjacent the contact 24a and a branch 283 leading to a terminal 248 adjacent the terminal 24b. The contacts 24a and 24B, 24b and 24B are so arranged with respect to the movable contacts 25 and 25' that, whenever current passes through the rectifier to the coil 2!, these contacts 25 and 25' willbe caused to move away from the terminals 2 a and 24b and and 8 are connected to the house current. however, the relay coil 2| will connect conductors 28A and 283 to the contacts 25 and 25', respectively, so that current from the rectifier will operate the vacuum tubes in the receiver. When the leads 8 and 9 are disconnected from the house circuit the contacts 25 and 25' will be released by the coil 2| and fall back upon contacts 24a and 24b, and the batteries will furnish the electrical energy needed.

'Io lead 3! is Joined a resistance 33, between the switch arm 32 and terminal 2, and this resistance is also connected to the lead 22 between the relay coil 21' and negative pole l4 or the rectifier. A larger resistance 34 is connected to the terminal 5 at one end, and to the lead 22, adjacent the resistance 33 at the other end. The elements 3 and 34 constitute a divided biasing resistor, the end of the resistance 34 toward the terminal 5 being also Joined to a large resistance R united to the grids of. the receiver shown diagrammatically at G. "I'he resistances 33 and 34 are such that suitable and substantially equal biasing voltage will be applied to the receiver from either the batteries or from the rectifier ll.

In the lead 21 is an inductive reactance- 25, at the ends or which a pair or condensers 36 are bridged across to the return wire 22. This provides an electrical filter for uni-directional current which the rectifier produces. The conductor 23A also has a suitable resistance 29 therein between the inductive reactance 35 and contact 24A to insure the proper voltage on the receiver cathodes, and another condenser 31 is joined across the return wire 22 and the WireZBA between the resistance 29 and terminal 24A, for extra filtering efiect. Any other suitable filter means, may be employed.

when house current is employed, the current returns to the rectifier pole I4 by way of the negative lead 22; and both filament and plate currents pass through the resistor 33 only; and the resistor 34 then serves merely as a slightly addi panam 3 as developed at the junction oi the two resistances 83' and 34. But when the batteries are used, --both resistances and tdconstitut'e'the bias resistance. The negative return is to terwith any portion oi the radio set or batteries because of this method of rectifier connection. Thus no accidental connection of the receiver chassis or parts thereof to ground can cause and, the potential developed on thegrid by the opened except when 'ho'usef' current is -alctually energizingthereceiverl wnenco nectarpmg l2 i is insertedinto a'house' supply'outl'et thuscon nectirig the leads 8 and 9,-the rece'iver will conminal B and negative lead 22thus becomes dead 6' damage when housecurrent is used; nor is it ended toanode I8. Thusalar'g er bias'resistnecessary toinsulate the terminal oi" plug ll "when the setjis used on batteries.

' Alibi the circuits and all of the parts connectresistances 33 and 34 together has the same value ed to the rectifier may be located in a housing as the potential produced by the resistance" 33 10 with the receiver, and may be easily carried from alonewhen house current is'usedI place toplace while continuing to operate, and, Thejunctionjpoint oi the 3 3 and 34, when ..used indoors or in any 'place where wiring anceis provided when batterycurrent is used,

' the batteries incircuitconnecis with thene'gapresent, the batteriesmay be conserved by tive pole" H of the house current-rectifier cir- "merely co'nnecting the set tohouse'current withcuit, which is completely isolated 'from'the con- 15f out manuallycperating'any switch,1and with the ductors 8 and 9,and thus nodrain is imposed on i j assurance that the polarity of the connector plug the batteries; nor can a shortfcircuit, imposed by hudfthe character oi 'the house current need'not accidentalconnection oi groundor' other points fibeconsidered. V to theleads B -'and 9, cause any-damage Instead oi a tube rectifier as shown it will be In order to indicate when therectifier current 20' understood that other types of rectifying m ans is energizing thesetand-that'ithebatteries are ,f mayjbeused.

, cutout I bridge. a small neon light 38 across the poles oitherectifier. After connection=is made ff flt will'be seen that my invention may be employed' with various apparatus; for example an to house-current the-set continus'ft'd-operate, a pli y svstemco mu c t syste s, etcirom thebatteries i'or a tew' moments. Illuminags :j VYh'en previouslylmown portable sets are "contion of'the neon light bulb 'indicat'sthatthe batp tohou'sejcurrentfthere is a period of sevtery circuit is open and the 'se't is operating on eralj'seoonds when no reception'is possible, while house current.

the jrectifler cathode heat'eirs' are being heated.

In the operation or a radio receiver with my "in such sets the house current and battery cirj transmission circuit it will be that one onlyr ao "cuits have been-separate and independent; nn needsto closethe on and "oii switch 32in important advantageo my apparatus lies in'the order to immediately energlze"the receiverand tactthatsince the batteriesare operatively concommence reception. Whenswitch -fl is closed, :nected until the house currentheats the rectifier and the'leads Sand! are not -joi'ried.'to a house j l cathodeheaters to render the rectifiers operative current supply system the set operate on 5' to; operate the relay ii; there need be no interbattery current since the batterycircuit'is closed ruption in reception, either when shifting from when theswitch'n is closed The battery circuit pnesource ct energyto the other, or when origiremains 'closed'jati aIFtime's" uiitil' switcu 32 is nallyiturning' on' the' set, f I

-';'I husthat'by my invention an eitremelysimplfdependable and convenient apparatus is provided.,* f f In summary, therefore, the arrangement of the drawing provides, in a radio receiver including tinue operating on battery *current until the v cathode heaters of the rectifier have beenheated vacuum-tubes in'the signal-translating channel by the house supply current when relay coil 2l I-1' therebf,'8 battery circuit including either of the 'will become energized and breakth'e battery 012 cults and close. the circuit through the rectifier, whereby the set will continue to operate, without substantial interruption, using energy'irom the house circuit supply. Whenconnector plug I2 is withdrawn from the house supply circuit outlet," disconnecting leads a and 91mm the house supply-current, the relay 2| will bereleas'ed' and will immediately 'break the'circuit-throughthe rectifier and close the battery circuitsand-theset. will continue to operate, without substantial in terruption, using power-"supplied from the battery circuits.

The rectifier I0 is: energized without transformers and the'terminafl! is always the positive' pole thereof. Hence jevenwhenthe rectifier is connected to' a direct current circuit it makes no difference which terminal-oi the plug is united to the positive side'o't the line. It the I terminal oi lead 8 is connected to the positive side of a directcurrent house supply circuit, can

rent will flow out of the rectifier from thepole l3, and ii the terminal oilead' 8 should be connected to the positive side ofthe supplycircuit the current will again 'fiowcutoi the rectifier fromthe'point l3 and henc correct connection to the house wiring is always assured and positive voltages will always be imposed upon the prises means responsive to the energization of the sets a: terminals I, 2 and 5, G and the conductors receiver. The arrangement also comprises a power-supply circuit, including conductors 8 and 9, which is connectable to a power line for supplying power to the tubes of the receiver to opcrate the receiver, as well as means, including the relay having winding 2|, for selectively connecting the battery circuit or the power-supply circuit to the tubes of the receiver. The arrangementalso comprises means responsive to the energ'ization or the power-supply circuit from the power line for energizing the winding 2| thereby mi to'actuate the connecting means, including the relay. to disconnect the battery circuit from the tubesoi the receiver during operationoi the receiver by power from the power lines. Furthermore, it will be seen that the arrangement com power-supply circuit including conductors 8, 9

from the power-supply line for normally connecting the battery circuits to the tube for operation'theretrom upon the operation of the switch 32 tothe 'on position and for efiectively disconnecting the battery circuits from the tubes and for connecting the tubes of the receiver for peration by power from the power line as soon as 3 terminals! and I. i It will be that conducn t r 't and 8 are insulated from direct connection of thereceiver have a given cathodesuch power is available. Specifically, the vacuheating time and the vacuum-tube power-supply means including rectifier I! has a cathode heating time substantially greater than that of the tubes 01 the receiver so that, upon placing the radio receiver in operation, power is supplied to operate the receiver from the battery circuit until such time as power is available from the rectifier circuit at which time the relay operates to condition the receiver for operation from the power-supply line.

What I claim is:

1. An electrical power supply circuit for connection with a radio receiving set, comprising, in combination, means for enabling said set to be operated from batteries, means for impressing direct or alternating house supply current on a bridge rectifier, means responsive to the energization of said set by said house current for disconnecting said batteries while said bridge rectifler is operative, and a portion of said means for providing grid potential being utilized in the connection between said output terminals and said batteries.

- means to said power line, and means responsive said circuit to energize said set without regard to the polarity of the means for connecting said circuit to the house supply current, and means responsive to the energization of said circuit by said house supply for rendering-said first means inoperative while said second means is operative.

2. An electrical power transmission circuit for connection with a radio receiving set, comprising, in combination, means for enabling said set to be operated either from batteries or from direct or alternating house supply current, and means responsive to the energization of said circult by said house supply torshirting the connections from batteries to house current and from house current to battery upon the insertion or withdrawal of a house connector plug and without the manual operation 01' any switch,

other than an on" and o'i!"' switch oi'the radio 3. A circuit 'for'supplying electricalenergy including, in combination, a plurality otbatteries,

means for connection to house current, a, single switch for simultaneously'closing the circuit through the batteries and for closing the circuit through the said means for connectionto house selectively connecting said battery circuit or said power-supply circuit-to said tubes, and means responsive to the energization of said powerto power from said power line for disconnecting said battery from said set to insure that said battery is disconnected from said set during operation of-said set by power from said power .line,

whereby said set may be operated by said battery operate said receiver, a power-supply circuit connectible to a power line for supplying power to said tubes to operate said receiver, means for supply circuit from a power line for actuating said connectingimeans to disconnect said battery from said tubes during operation of said receiver by power from said power line.

8;-In a radio receiver including vacuum tubes the signal-translating channel thereof, a batcircuit for supplying power to said tubes to operate said receiver, an on-ofl switch for said 'receiver, a power-supply circuit connectible to appo'w'er line for supplying power to said tubes [to-operate said receiver, means for selectively means for connection to house current is'operatively connected to house current and to close said circuit when said means for connection to house current is disconnected from house current. x"

4. An electrical circuit for connection with a radio receiving set, comprising, in combination, means for enabling said set to be operated from batteries, means for impressing direct or alternating current from an additional source on said circuit to energize said set, means responsive to the energization of said circuit by said additional source for opening the connections between'said batteries and the set and for closing the cameo-- tions to the set of the additional source upon the insertion of a connector plug to said additional source, without regard to the polarity of said plug, and without the operation of any other switch than the "on and off switch of the radio set. u

5. A circuit for supplying electrical energy to a radio receiver including tubes having grids, comprising, in combination, a plurality of batteries, means for connection to house current, output terminals, connections between said output terminals and said batteries for enabling said set to be connecting 'said battery circuit or said powersupply' circuit to said'tubes, and means responsiveto theenergization of said power-supply circuit from said power-supply line for normally connecting said battery circuit to said tubes for operation-therefrom upon the operation of said switch to said,on" position and for effectively disconnecting said battery circuit from said tubes and connecting-said receiver for operation by operate said receiver, means responsive to the operated from said batteries, means for providing suitable potential for the grids of said tubes, connections between said output terminals and'said means for connection to house current including energiz'ation of said power-supply circuit from said power-supply line for connecting said power-supply circuit-to said power-supply line and for eiiectively disconnecting said battery circuit from said tubes during operation of said receiver by power from said power line.

10. In a' radio receiver including vacuum tubes in the signal-translating channel thereof, a battery circuit for supplying power to said tubes for operation of said receiver, a power-supply circuit connectible to a power-supply line for supplying power to said tubes to operate said receiver, means for selectively connecting said am said receiver, a vacuum-tube battery circuit or said power-supply circuit to said tubes, and means responsive to the energization of said power-supply circuit from said.

power-supp y line for efiectively disconnecting said battery circuit from said tubes and connecting saidpower-supply circuit to said tubes as soon as power is available for operation of said receiver from said power line.

11. In a radio receiver including in the signaltranslating channel thereof vacuum tubes having given cathode heating times, a battery circult for supplying power to said tubes to opermeans having a cathode heating time substanpower-supplv means for selectively tially greater than that of said tubes' and connectibie to a power-supply line for supplying power to said tubes to operate said receiver, connecting said battery circuit or said power-supply means to said tubes, and means responsive to the energization of said power-supply means from said power-supply line for actuating said connecting means to disconnect said battery circuit from said tubes and to connect said power-supply means to said tubes as soon as power is available for operation of saidreceiver from said power-supply line.

' TOWNSEND s. JONES. 

